Guildford Castle Park is a beautiful garden just a few minutes walk from the city center. It was built on a hill overlooking the river and the two-story houses of the center. The castle can be visited but it's quite small and isn't really worth it. The gardens, however, are very well-kept and beautiful, no matter the season. It opens at sunrise and closes at sunset and, of course, varies depending on the season. The young people of the city often gather here to have lunch and on the weekends there's a small orchestra that plays classical music or jazz. The castle is from the 11th century and served to protect the city from invasions.